1. Field of the Invention
The present invention relates to a continuous magnetic tape, comprising a magnetic tape of which both ends are connected together to form a continuous loop. The magnetic tape is arranged in different configuration by various mechanisms. The magnetic tape can be of various lengths providing recording time from a few seconds to a number of minutes according to its purposes.
2. Discussion of the Prior Art
FIG. 1 is a plane view partly cross-sectioned of a conventional endless audio magnetic cassette tape which has been widely used in answering phone machines. Wherein a reference numeral 1 designates a magnetic tape of which both ends are connected together to form a continuous loop.. Numeral 2 designates a casing. Letter T designates a magnetic tape reel. Numerals 22 and 32 designate two holes for the driving shafts of the recording apparatus. Letter E designates a hub disposed in casing 2. When this audio endless cassette tape is mounted on a recording apparatus to play, two guide posts formed in the recording apparatus are inserted in reference holes 6, an erase head moves into the window 5, a recording/playing head moves into window 7, and the two driving shafts of the recording apparatus are inserted into the holes 22 and 32. The rotation of the driving shafts does not affect the inside mechanism of the tape. Further, a capstan shaft of the recording apparatus is fitted to the aperture 8, and a pinch roller pushes the magnetic tape 1 against the capstan shaft through the window 9. The rotation of the capstan shaft and pinch roller pulls the magnetic tape 1 from the guide roller 4 to guide roller 10 under the condition that the magnetic tape 1 is held by the pinch roller and the capstan shaft. The magnetic tape 1 is wound loosely around the hub E to form a reel T, so loosely that it can be pulled out from the center of the reel T, feeding askew, so that it passes across the reel T. As the magnetic tape 1 is transported past the recording/playing head by the action of the capstan and pinch roller, it continues to pull from the center of the reel T, rotating the reel T as it does so. The magnetic tape is fed back onto the outside of the reel T, providing its own take up. The magnetic tape is continuous. When the magnetic tape runs in contact with the recording/playing head of the recording apparatus, an electromotive force is reproduced in the coil of the recording/playing head. An output for reproducing the message is obtainable.
The magnetic tape should not fit tightly, but neither should it be loose. On the other hand, if pulling the magnetic tape 1 from the center of the reel T causes the magnetic tape 1 being fed back onto the outside too tighten, the magnetic tape 1 will jam. The edge of the magnetic tape 1 is easily damaged by friction which is taken place, while the magnetic tape 1 is pulled out from the center of the reel T. The magnetic tape 1 handling must be carefully controlled, even a slight buckling of the tape fed to the outside of the reel T will increase the diameter of the outside turn. The reel T will start taking up the slack faster than it is drawing tape from the center of the reel T. As this continues, more of the reel T will have a larger turn size than original until again the magnetic tape 1 jams. This cassette tape can not be used either side up.
FIG. 2 is a plane view partly cross-sectioned of a video magnetic cassette tape which has been widely used. Reference numeral 51 designates a magnetic tape. Numeral 52 designates a casing. Numeral 91 designates a window for capstan shaft and pinch roller of the recording apparatus. Numeral 53 designates a take up guide roller formed in casing 52. Numeral 92 designates a take up guide formed in casing 52. Numeral 85 designates a supply guide roller. Numerals 55 and 75 designate two drums respectively, which are disposed in the casing 52. Numerals 54 and 74 designate two center pieces of the two drums 55 and 75. Letter G designates the supply reel.
When this video magnetic cassette tape is inserted into a video recording apparatus to play, two driving shafts of the video recording apparatus will be inserted into the two center places 54 and 74 of the two drums 55 and 75 respectively; the two center places 55 and 74 have little pins projecting inwards. These pins engage with the projections on the driving shafts. Thus a rotational force is applied to drum 55, which rotates clockwise. The magnetic tape is wound onto the take-up drum 55 under tension. Furthermore, a capstan shaft of the video recording apparatus is fitted to the window 91, and a pinch roller pushes the magnetic tape 51 against the capstan shaft through window 91. The rotation of the capstan shaft and the pinch roller pulls the magnetic tape 51 through the tape path from the supply guide roller 85 to the take up guide roller 53. The magnetic tape 51 comes off supply reel G, passes over the supply guide roller 85, and runs in contact with the erase head and the video drum which houses the video heads. The magnetic tape 51 is wound onto the drum 55. The signals on magnetic tape 51 are read by video heads and an audio/control head. The ends of the magnetic tape 51 are fastened on the drums 55 and 75, so there must be a limited playing time. When the magnetic, off the supply reel, reaches its end, it has to be rewound to be played again. This video cassette tape can not be used either side up.